Installed PVC closet flange 1/2 inch above concrete floor, allowing for quickset and ceramic tile installation. Due to the drain pipe pitch, the flange is slightly off-level and canted approximately 1/4" above the finished floor level. Will this be a problem for proper leveling and installation of the toilet, or will the wax seal compensate? Only other alternative is to bust out concrete sub-floor and re-do the rough-in. Any advice? Thanks

Should be OK. Set toilet and see if it sits flat on floor. Wax ring will form to fit.

Most toilets have a recessed area under the bowl that allows some room to play with. Like Harold said, "Wax ring will form to fit."... ;)

You should be all set.

MARK